Hash Function

Hash functions are the backbone of cryptographic security in blockchain networks. They take an input (like a transaction or file) and produce a unique hash output. Even a minor change in the input drastically alters the output—a feature called the avalanche effect. In blockchains like Bitcoin, hash functions link blocks by embedding the hash of the previous block into the current one, forming a secure, tamper-evident chain. They are also used in mining, where miners compete to find a hash below a certain threshold to add new blocks. In Ethereum, Keccak-256 is widely used. Hash functions also help generate digital signatures and validate Merkle Trees for efficient data verification. Their role in maintaining decentralised consensus, security, and transparency is indispensable.